It is an unassuming thing at first glance, barely a third of a metre high, but its upper surface holds a carved depression nearly half a metre across and almost a quarter of a metre deep, a proportion that makes it unusually hollow relative to the modest bulk of the stone. This is a bullaun, a type of early medieval stone with one or more cup-shaped hollows whose precise function remains debated, though associations with grinding, ritual use, and curative practice recur across Irish monastic sites. What makes this particular example quietly remarkable is that it is one of a matched pair, a second almost identical boulder lying less than a metre to the south, the two so closely alike in shape and in the placement of their depressions that they seem to have been arranged or selected with some deliberate purpose.

Excavations carried out in 1977 under the direction of de Paor opened a four-metre square cutting around the first bullaun and turned up a dense and varied scatter of material in the upper layers: whetstones, knife-blades, nails, clay pipe fragments, burnt bone, mortar, slag, and chert chippings. The soil around both stones was heavily mottled with charcoal and burnt material, suggesting repeated activity over a long period. An extension of the cutting in 1979 brought the second bullaun to light. Among the finds was a fragment of a stone pestle, which may have been used within the hollows themselves, pointing toward some kind of grinding or processing function, though whether that was medicinal, culinary, or ceremonial is impossible to say from the material alone. McNamara, writing in 1984, noted the strong resemblance between the two boulders and the consistent positioning of the depressions, which raises the possibility that the pairing was intentional rather than coincidental.